Ten major users request funds to provide integrated instrumentation that will provide the ability to carry out state-of-the-art cryo-fixation and immunounolabeling at both the level of light and electron microscopy. These instruments include a Leica Ultracut UCT microtome with an FSC cryo-attachment. Diatome diamond knives, an Edwards auto 306 high vacuum deposition system configured for electron microscopy, a Bal- Tec Jet Freeze device and a Bal-Tec Freeze substitution unit. This instrumentation will be placed in a central EM-facility that is co- sponsored by the Department of Cellular and Structural Biology and the Cancer Center. They will provide renovated space for the equipment, hire Dr. Jan Slot of the University of Utrecht in the Netherlands to provide training to our scientists already skilled in microtomy and provide for the continued care of the instruments. The ten investigators are addressing various biological questions and each would benefit from improving the quality of their light and electron microscopy by application of rapid freeze fixation techniques. Their projects all require immunolocalization at the EM-level and the ability to prepare and label Tokuyasu-ultrathin cryo sections will enhance their NIH funded research. Importantly this instrumentation will facilitate the research of many other investigators in the Health Sciences Center who require EM-immunolabeling and use of well preserved cells and tissues for study using a variety of morphological techniques. The high vacuum deposition system is necessary to prepare grids and coat/shadow molecules and macromolecular complexes for optimal visualization with the electron microscope. Comparable instruments are not currently available at the Health Sciences Center. The group of scientist on this SGI has a history of collegial interactions, a background that argues well for the successful sharing of the instrumentation requested.